Algebra is used for mathematics
structural engineering
PYTHAGORAS
He proved the "fundamental theorem of algebra" and developed a method of minimizing statistical error called "the method of least squares" which is still used today.
yes it is still used today
the tank is still used today. For example the M1 Abrams is still used
long houses are not still used today
The theorem of Pythagoras is used in mathematics (primarily in trigonometry and geometry), physics (for a variety of things) and is also employed in architecture and design. it is also used to find any side of a right angle triangle
Yes, the corollary to one theorem can be used to prove another theorem.
yes it is still being used today.......depends where your at.
Yes teepees are still used today by uncommon are unknown idians.
Yes, trains are still being used today in large quantities.